Psych::ScalarScanner#parse_time

# File tmp/rubies/ruby-4.0.0/ext/psych/lib/psych/scalar_scanner.rb, line 115
def parse_time string
  klass = class_loader.load 'Time'

  date, time = *(string.split(/[ tT]/, 2))
  (yy, m, dd) = date.match(/^(-?\d{4})-(\d{1,2})-(\d{1,2})/).captures.map { |x| x.to_i }
  md = time.match(/(\d+:\d+:\d+)(?:\.(\d*))?\s*(Z|[-+]\d+(:\d\d)?)?/)

  (hh, mm, ss) = md[1].split(':').map { |x| x.to_i }
  us = (md[2] ? Rational("0.#{md[2]}") : 0) * 1000000

  time = klass.utc(yy, m, dd, hh, mm, ss, us)

  return time if 'Z' == md[3]
  return klass.at(time.to_i, us) unless md[3]

  tz = md[3].match(/^([+\-]?\d{1,2})\:?(\d{1,2})?$/)[1..-1].compact.map { |digit| Integer(digit, 10) }
  offset = tz.first * 3600

  if offset < 0
    offset -= ((tz[1] || 0) * 60)
  else
    offset += ((tz[1] || 0) * 60)
  end

  klass.new(yy, m, dd, hh, mm, ss+us/(1_000_000r), offset)
end